Sino-French War

The Tonkin War, also called the Sino-French War was a military conflict fought between the French Empire and the Qing Dynasty from 1884 to 1885. With the first shots fired in 1883 when the French seized Hanoi, the French and Chinese fought a border war that eventually led to France gaining full control of Vietnam.

War
With the southern Vietnamese provinces of Cochinchina already under their control, in the 1880s the French began to encroach northward into areas under Chinese control. China responded by sending forces into the river delta that formed the core of Tonkin in northern Vietnam. Both sides accused the other of aggression, and French captain Henri Laurent Riviere was sent into Hanoi, the administrative center of Tonkin, to evict the "Black Flag Pirates", Chinese irregular troops who were occupying the city. Riviere expelled the Chinese but was killed in a counterattack. French reinforcements arrived and quickly won a series of battles, forcing the Chinese viceroy to negotiate an agreement under which the area would become a joint Sino-French protectorate. When the agreement was rejected in Paris, China declared war, confident that its newly equipped army would repel the invaders. Chinese ground forces led by Chang Chih-tung held off French incursions into southern China, but the hard reality about Chinese modernization was exposed in the battle of Fuzhou in August 1884. In the space of half an hour, an entire new fleet of Chinese cruisers was utterly destroyed by French naval firepower and torpedo boats. China had no choice but to surrender both Tonkin and, farther south, Annam to the French.